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Early holocene openlands in southern New England
E K Faison1, D R Foster, W W Oswald
1Harvard Forest, Harvard University, Petersham, Massachusetts 01366, USA. faison@fas.harvard.edu
Ecology
|November 9, 2006
Summary
Large mammals did not create early Holocene openlands in New England. Instead, dry conditions and fire likely maintained these habitats, with modern open areas stemming from Colonial agriculture.
Area of Science:
- Paleoecology
- Palynology
- Ecology
Background:
- The Holocene vegetation structure of temperate forests is debated, particularly Frans Vera's hypothesis on large mammal-induced openlands.
- Previous research debated the origin of abundant ragweed pollen in early Holocene New England.
Purpose of the Study:
- To investigate the origin of early Holocene ragweed pollen in southern New England.
- To provide insights into the debate on prehistoric openland vegetation structures.
Main Methods:
- Analysis of new pollen records from Harvard Forest and the North American Pollen Database.
- Comparison of early Holocene pollen assemblages with modern records and paleoclimate data.
Main Results:
- Ragweed and forb pollen exceeded 3.5% in southern New England between 10,100 and 7700 years BP.
- Pollen data suggest local origins and association with oak-pine forests, dry conditions, and fire.
- Early Holocene openlands lack modern analogues in New England, with current open areas originating from Colonial agriculture.
Conclusions:
- Early Holocene openlands in New England were likely maintained by climate and fire, not large mammals.
- Modern openlands are primarily a legacy of Colonial agriculture and require specific management.
- Findings may inform forest dynamics under projected arid climate change.
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